National 5 Chemistry in Society

Transcription

1 National 5 hemistry in Society Name Test What is the percentage by mass of aluminium in aluminium oxide, l 2 O 3? 40% 53% 62% 66% 4. In the experiment below Which ion gives a pink colour with ferroxyl indicator? OH - (aq) Fe 2+ (aq) Fe 3+ (aq) Mg 2+ (aq) 2. Which of the following elements is most likely to be obtained by electrolysis of its molten compounds? alcium Gold Iron Zinc Electrons will flow from Tin to zinc through the wire Zinc to tin through the wire Tin to zinc through the ion bridge Zinc to tin through the ion bridge

2 5. Which of the following metals reacts vigorously with acid? 8. Monomers used to make addition polymers must be Magnesium Silver Lead Tin carbohydrates hydrocarbons saturated unsaturated 6. In which of the following situations will the iron be protected from rusting? Lead pipes connected to iron pipes. opper nails used to support iron sheets. Iron plates held by copper rivets Zinc nails used to support iron sheets 7. Which of the following cells would produce the highest voltage? (You may wish to use page 7 of the data booklet to help you.) 9. Polyethene is a synthetic addition polymer a natural addition polymer a synthetic condensation polymer a natural condensation polymer 0. Which of the following salts can be prepared by precipitation? calcium nitrate calcium chloride silver chloride nickel sulphate. Which of the following is not afertiliser? Potassium sulphate Sodium chloride Sodium nitrate Sodium phosphate 2. sample of polluted water gives a green flame colour. Which element must be present in the water? alcium opper Potassium Sodium 2 National 5 hemistry

3 3. When superglue sets, a polymer is formed. Part of the polymer structure is shown. H N H N H N H OOH 3 H OOH 3 H OOH 3 raw the structure of the repeat unit in the superglue polymer. The polymer shown above contains methyl groups ( H 3 ). nother type of superglue, used to close cuts, has the methyl groups replaced by either butyl groups ( 4 H 9 ) or octyl groups. omplete the table to show the number of carbon and hydrogen atoms in an octyl group. Name a toxic gas made when superglue burns. (3) National 5 hemistry

4 4. pupil carried out a titration using the chemicals and apparatus below. Using the results in the table, calculate the average volume of hydrochloric acid required to neutralise the sodium hydroxide solution....cm 3 The equation for the reaction is: NaOH + Hl ---> Nal + H 2 O Using your answer from part, calculate the concentration of the sodium hydroxide solution....moll - 2 (3) National 5 hemistry

5 5. pupil set up the following cell. ombine the two ion-electron equations for the electrode reactions to produce a balanced redox equation. What is the purpose of the ion bridge? escribe the chemical test which could be used to show that iodine is formed at electrode. (3) National 5 hemistry

6 6. Energy is required to remove an electron from an atom. The graph shows the energy required to do this for the first 9 elements. escribe what happens to the energy required going down a group. escribe the general trend in the energy required going from sodium to argon. raw a bar on the graph to show the energy you would expect to be required for the element with atomic number 20. (3) National 5 hemistry

7 7. Thorium 227 decays by alpha emission. omplete the nuclear equation for the alpha decay of thorium Th ---> 90 sample of thorium-227 was placed in a wooden box. radiation detector was held 0 cm away from the box. Why was alpha radiation not detected? Thorium-227 has a half-life of 8 days. What fraction of the original radioactivity will remain in a sample which is 36 days old? (2) National 5 hemistry [Turn over

8 8. mmonia is produced in the Haber process. The percentage yield of ammonia, obtained at different pressures, is shown in the table. raw a line graph of the results. Use appropriate scales to fill most of the graph paper. Using your graph, estimate the yield of ammonia at 300 atmospheres....% Which two gases react to make ammonia i the Haber process? 2 Page eighteen National 5 hemistry (4)

9 National 5 hemistry